Okay, so Brandon has a mix of technical skills like engineering, interferometry, and fiber optics. His experience in testing and troubleshooting is also valuable. Location is Tucson, Arizona, which is a moderate-cost-of-living area. Considering his skills, I'd place him in the mid-to-upper range for an engineer. Looking at salary benchmarks, a senior engineer with similar skills in the US can earn around $100-$150 per hour. However, this rate is lower than what experts in similar fields might charge, like $200-$300 per hour. Given Brandon's experience and skills, I'd estimate his hourly rate to be around $125, which is slightly below the average but still competitive.